Abstract
Dysregulation of microRNAs (miRNAs) has been associated with malignant behavior in a variety of cancers. Our previous study demonstrated that miRNA expression profiles are predictors for patients with advanced non-small cell lung cancer (NSCLC). We also showed that miRNAs are involved in small-cell lung cancer metastasis. Here, we used qRT-PCR to re-analyze our previous microarray results using serum samples from 75 patients with NSCLC. Surprisingly, we found that miR-574-5p and miR-874 were overexpressed in patients with metastatic advanced NSCLC but not in patients with non-metastatic advanced NSCLC. Additionally, miR-574-5p expression was correlated between matched serum and tissue samples from 68 patients. However, these 2 miRNAs are not prognostic factors for NSCLC. Transwell and wound-healing assays showed that miR-574-5p promotes the migration and invasion of NSCLC cells. Furthermore, miR-574-5p enhanced the tyrosine phosphorylation of β-catenin by repressing PTPRU expression in vitro. In conclusion, this study explored the expression of miR-574-5p in clinical samples and its molecular mechanisms in the metastasis of advanced NSCLC.